Re: [PATCH v3 2/5] iommu/s390: support cleanup of additional table regions

[Niklas Schnelle <schnelle@linux.ibm.com>]

On Fri, 2025-02-28 at 16:44 -0500, Matthew Rosato wrote:
> Extend the existing dma_cleanup_tables to also handle region second and
> region first tables.
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
> ---
>  drivers/iommu/s390-iommu.c | 71 ++++++++++++++++++++++++++++++++++----
>  1 file changed, 64 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
> index cad032d4c9a6..f2cda0ce0fe9 100644
> --- a/drivers/iommu/s390-iommu.c
> +++ b/drivers/iommu/s390-iommu.c
> @@ -121,6 +121,22 @@ static inline int pt_entry_isvalid(unsigned long entry)
>  	return (entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID;
>  }
>  
> 
--- snip ---
> +
> +static void dma_cleanup_tables(struct s390_domain *domain)
> +{
> +	int rtx, rsx, rfx;
> +
> +	if (!domain->dma_table)
>  		return;
>  
> -	for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
> -		if (reg_entry_isvalid(table[rtx]))
> -			dma_free_seg_table(table[rtx]);
> +	switch (domain->origin_type) {
> +	case ZPCI_TABLE_TYPE_RFX:
> +		for (rfx = 0; rfx < ZPCI_TABLE_ENTRIES; rfx++)
> +			if (reg_entry_isvalid(domain->dma_table[rfx]))
> +				dma_free_rs_table(domain->dma_table[rfx]);
> +		break;
> +	case ZPCI_TABLE_TYPE_RSX:
> +		for (rsx = 0; rsx < ZPCI_TABLE_ENTRIES; rsx++)
> +			if (reg_entry_isvalid(domain->dma_table[rsx]))
> +				dma_free_rt_table(domain->dma_table[rsx]);
> +		break;
> +	case ZPCI_TABLE_TYPE_RTX:
> +		for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
> +			if (reg_entry_isvalid(domain->dma_table[rtx]))
> +				dma_free_seg_table(domain->dma_table[rtx]);
> +		break;
> +	default:
> +		WARN_ONCE(1, "Invalid IOMMU table (%x)\n", domain->origin_type);
> +		return;
> +	}
>  
> -	dma_free_cpu_table(table);
> +	dma_free_cpu_table(domain->dma_table);
>  }
>  
>  static unsigned long *dma_alloc_page_table(gfp_t gfp)
> @@ -358,7 +415,7 @@ static void s390_iommu_rcu_free_domain(struct rcu_head *head)
>  {
>  	struct s390_domain *s390_domain = container_of(head, struct s390_domain, rcu);
>  
> -	dma_cleanup_tables(s390_domain->dma_table);
> +	dma_cleanup_tables(s390_domain);
>  	kfree(s390_domain);
>  }
> 

Looks good to me.

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>